The present disclosure relates to virtual area network (VLAN) membership management in a hybrid wired and wireless digital network. In particular, the present disclosure relates to management and configuration of VLAN memberships associated with applications or network protocols.
Wireless digital networks, such as networks operating under IEEE 802.11 standards, are spreading in their popularity and availability. With such popularity, however, come problems of managing Virtual Area Network (VLAN) memberships associated with specific applications or network protocols, e.g., VLAN membership management in a broadcast or multicast dependent process, such as stateless autoconfiguration.
VLANs are logical local area networks (LANs) based on physical LANs. A VLAN can be created by partitioning a physical LAN into multiple logical LANs or subnets using a VLAN identifier. Alternatively, several physical LANs can function as a single logical LAN. Multiple VLANs can be on either a single router or multiple routers. Hosts within a VLAN communicate as if they were attached to the same broadcast and/or multicast domain regardless of their physical locations. Because packets are only delivered between network ports that are designated to the same VLAN, VLAN reduces network traffic and avoids wasting bandwidth, especially in LAN environments with applications or network protocols that require broadcast and/or multicast support.
Stateless autoconfiguration allows various network devices attached to an Internet Protocol version 6 (IPv6) network to connect to the Internet without requiring any intermediate IP support from, e.g., a Dynamic Host Configuration Protocol (DHCP) server. The stateless autoconfiguration is defined in Internet Engineering Task Force (IETF) Request for Comments (RFC) 2462. At the startup of stateless autoconfiguration, a wireless station automatically creates a link-local address on each IPv6-enabled interface. IPv6 hosts typically use Neighbor Discovery Protocol (NDP) to create a globally routable unicast address based on router advertisement packet received from an IPv6 router. The global address is usually shared by all automatically configured addresses of the corresponding IPv6-enabled interface. Thus, only one multicast group needs to be joined for neighbor discovery.
Multiple VLAN memberships may cause undesirable consequences in a broadcast and/or multicast network setting. For example, in some network environments, an application or a network protocol may require broadcast and/or multicast support, and multiple wireless stations belonging to different VLANs can be associated with the same base service, e.g., the same access point. Ideally, a wireless station shall respond only to broadcast and/or multicast packets that are intended for the wireless station to receive (e.g., the broadcast and/or multicast packets from the same VLAN that the wireless station belongs to) and discard other received packets. However, under current wireless local area network (WLAN) standards, information about VLAN memberships are not transmitted within the broadcast and/or multicast packet to wireless stations. Therefore, a wireless station cannot distinguish broadcast and/or multicast packets received from different VLANs, which may cause undesirable consequences.